B279A

ENGINE IMMOBILISER: ENGINE IMMOBILISER SYSTEM: B279A: Theft Deterrent System Communication Line High Fixation
B279A - Theft Deterrent System Communication Line High Fixation

DESCRIPTION

If the communication line (EFIO-IMI) to the transponder key ECU is stuck on HI output, the ECM outputs this DTC.

WIRING DIAGRAM

INSPECTION PROCEDURE

NOTICE:
- If the transponder key ECU assembly is replaced, register the key and ECU communication ID Programming and Relearning.
- If the ECM is replaced, register the ECU communication ID Programming and Relearning.
PROCEDURE

1. CHECK DTC OUTPUT

(a) Recheck for DTCs Engine Immobiliser System.

HINT
If any DTCs other than DTC B279A are output, troubleshoot those DTCs first.

Result:

A -- GO TO DTC CHART Engine Immobiliser System
B -- Continue to next step.

2. CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - ECM)

(a) Disconnect the D23 transponder key ECU connector.

(b) Disconnect the A21 ECM connector.

Standard Voltage:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

3. PERFORM ACTIVE TEST USING ECM (INPUT)

(a) Reconnect the transponder key ECU assembly connector.

(b) Reconnect the ECM connector.

(c) Measure the waveform.

Waveform 1 (Reference):

OK:

Normal waveform is output

NG -- REPLACE ECM Removal
OK -- Continue to next step.

4. REPLACE TRANSPONDER KEY ECU

(a) Replace the transponder key ECU assembly Removal.

NEXT -- Continue to next step.

5. REGISTER KEY

(a) Register the key Programming and Relearning.

NEXT -- Continue to next step.

6. REGISTER ECU COMMUNICATION ID

(a) Register the ECU communication ID Programming and Relearning.

NEXT -- Continue to next step.

7. CHECK DTC OUTPUT

(a) Clear the DTCs Engine Immobiliser System.

(b) Recheck for DTCs.

OK:

B279A is not reoutput.

NG -- REPLACE ECM Removal

OK -- END (TRANSPONDER KEY ECU IS DEFECTIVE)